From f16acc9d9b3761ae5e45219c9302f99e20919829 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Wed, 5 Jun 2019 08:04:47 -0700 Subject: vfs: introduce generic_copy_file_range() Right now if vfs_copy_file_range() does not use any offload mechanism, it falls back to calling do_splice_direct(). This fails to do basic sanity checks on the files being copied. Before we start adding this necessarily functionality to the fallback path, separate it out into generic_copy_file_range(). generic_copy_file_range() has the same prototype as ->copy_file_range() so that filesystems can use it in their custom ->copy_file_range() method if they so choose. Signed-off-by: Dave Chinner Signed-off-by: Amir Goldstein Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/fs.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index f7fdfe93e25d..ea17858310ff 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1889,6 +1889,9 @@ extern ssize_t vfs_readv(struct file *, const struct iovec __user *, unsigned long, loff_t *, rwf_t); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); +extern ssize_t generic_copy_file_range(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t len, unsigned int flags); extern int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count, -- cgit v1.2.3 From a31713517dac0862a3f0ec9006df9160ce022b0c Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 5 Jun 2019 08:04:48 -0700 Subject: vfs: introduce generic_file_rw_checks() Factor out helper with some checks on in/out file that are common to clone_file_range and copy_file_range. Suggested-by: Darrick J. Wong Signed-off-by: Amir Goldstein Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/fs.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index ea17858310ff..89b9b73eb581 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3049,6 +3049,7 @@ extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *); extern int generic_remap_checks(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count, unsigned int remap_flags); +extern int generic_file_rw_checks(struct file *file_in, struct file *file_out); extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *); extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *); extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *); -- cgit v1.2.3 From 96e6e8f4a68df2d94800311163faa67124df24e5 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 5 Jun 2019 08:04:49 -0700 Subject: vfs: add missing checks to copy_file_range Like the clone and dedupe interfaces we've recently fixed, the copy_file_range() implementation is missing basic sanity, limits and boundary condition tests on the parameters that are passed to it from userspace. Create a new "generic_copy_file_checks()" function modelled on the generic_remap_checks() function to provide this missing functionality. [Amir] Shorten copy length instead of checking pos_in limits because input file size already abides by the limits. Signed-off-by: Dave Chinner Signed-off-by: Amir Goldstein Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/fs.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index 89b9b73eb581..e4d382c4342a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3050,6 +3050,9 @@ extern int generic_remap_checks(struct file *file_in, loff_t pos_in, struct file *file_out, loff_t pos_out, loff_t *count, unsigned int remap_flags); extern int generic_file_rw_checks(struct file *file_in, struct file *file_out); +extern int generic_copy_file_checks(struct file *file_in, loff_t pos_in, + struct file *file_out, loff_t pos_out, + size_t *count, unsigned int flags); extern ssize_t generic_file_read_iter(struct kiocb *, struct iov_iter *); extern ssize_t __generic_file_write_iter(struct kiocb *, struct iov_iter *); extern ssize_t generic_file_write_iter(struct kiocb *, struct iov_iter *); -- cgit v1.2.3 From e38f7f53c35213b1cbce70eee5de7ced17f40d4a Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 5 Jun 2019 08:04:49 -0700 Subject: vfs: introduce file_modified() helper The combination of file_remove_privs() and file_update_mtime() is quite common in filesystem ->write_iter() methods. Modelled after the helper file_accessed(), introduce file_modified() and use it from generic_remap_file_range_prep(). Note that the order of calling file_remove_privs() before file_update_mtime() in the helper was matched to the more common order by filesystems and not the current order in generic_remap_file_range_prep(). Signed-off-by: Amir Goldstein Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- include/linux/fs.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index e4d382c4342a..79ffa2958bd8 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2177,6 +2177,8 @@ static inline void file_accessed(struct file *file) touch_atime(&file->f_path); } +extern int file_modified(struct file *file); + int sync_inode(struct inode *inode, struct writeback_control *wbc); int sync_inode_metadata(struct inode *inode, int wait); -- cgit v1.2.3